At present, with rapid popularization of networks and increasingly deepening of applications, various value-added services are widely deployed on networks, network bandwidth is increased exponentially, and network load balancing has increasingly become a focus of people's attention. A multi-gateway load balancing protocol is a protocol that is applied widely at present and can effectively solve a network load problem.
The Transparent Interconnection of Lots of Links (TRILL) protocol is a routing protocol based on link state calculation on a layer-2 network. The TRILL protocol is implemented by using the Intermediate System to Intermediate System (IS-IS) protocol, a device that runs the TRILL protocol is called a routing bridge (Routing Bridge) device, and a network formed by RBs is called a TRILL network (TRILL Campus). The RBs on the TRILL network, from a functional perspective, may be categorized into transit RBs and edge RBs. Each edge RB is responsible for routing data traffic forwarded by dozens of and even hundreds of servers. Each transit RB may route data traffic forwarded by multiple edge RBs. Edge RBs are categorized into ingress RBs and egress RBs. When an edge RB receives traditional layer-2 traffic sent by a server, encapsulates the received traditional layer-2 traffic by using the TRILL protocol, and sends encapsulated traditional layer-2 traffic to the internal of a TRILL network, the edge RB is an ingress RB; when an edge RB receives TRILL data traffic forwarded by a TRILL network, decapsulates and restores the received TRILL data traffic to traditional layer-2 traffic by using TRILL, and sends the traditional layer-2 traffic to a server, the edge RB is an egress RB. A typical TRILL network architecture includes a transit RB, an edge RB, and many servers. An RB on a TRILL network may be identified by a Nickname. A Nickname cannot be repeated on an entire network, and may be automatically generated or manually configured. Each RB establishes a unicast route that is based on a Nickname of another RB, and mutual communication may be implemented between different RBs through a Nickname-based unicast route.
In a TRILL network architecture nowadays, a multi-gateway load balancing protocol is generally used to perform traffic load balancing, that is, multiple transit RBs share a virtual Internet Protocol (IP) address, a transit RB is elected by negotiation, as an active virtual gateway, from multiple transit RBs, and the active virtual gateway separately allocates different virtual medium access control (MAC) addresses to other transit RBs. One virtual MAC address is allocated to each transit RB. Different servers separately establish connections, according to the different virtual MAC addresses, to different transit RBs through edge RBs, and separately send traditional layer-2 traffic to the different transit RBs, so that the transit RBs evenly share traffic load, thereby expanding TRILL network bandwidth, and avoiding a problem of TRILL network breakdown caused by a fault with an important RB (a transit RB that is mainly responsible for traffic load). An active virtual gateway establishes an information table of a server that is connected to each transit RB. When a transit RB is faulty, to ensure that a server connected to the transit RB properly accesses a TRILL network, the active virtual gateway sends information of the server connected to the transit RB to another transit RB. The another transit RB sends, by unicasting, an Address Resolution Protocol (ARP) packet to a server corresponding to the received information of the server. By using an ARP packet to notify newly connected servers of its virtual MAC address, a transit RB enables these servers to properly access a TRILL network.
In the foregoing scenario of multi-gateway load balancing on a TRILL network, the inventor finds that in the prior art at least the following problems exist:
A large quantity of servers access the TRILL network. When there are many servers connected to the faulty RB and these servers access the TRILL network through a new transit RB, the new transit RB sends, by unicasting, an ARP packet to each newly connected server; in this case, a lot of resources of the TRILL network are wasted, and particularly in a fault recovery scenario, a lot of resource overheads prolong fault recovery time and reduce fault recovery efficiency.